Energy recovery apparatus

ABSTRACT

An energy recovery apparatus for heating or industrial systems that entail the combustion of products, comprises a tubular element, which is arranged at a portion of a stack or flue and is provided with a delivery for feeding water for scrubbing exhaust gases. The tubular element has an outlet for collecting the treated water that can be conveyed to a heat exchanger. The apparatus allows reduction of the emission of particulates and pollutants into the environment and makes it possible to achieve a reduction in the temperature of the exhaust gases as well as heat energy recovery.

The present invention relates to an energy recovery apparatus.

BACKGROUND OF THE INVENTION

Currently it is known that boilers are used to heat water for residential and industrial uses.

These boilers are supplied by means of fuels which, by burning, release exhaust gases which are expelled by means of stacks or flues.

The combustion that occurs inside boilers inherently produces particulates and pollutants whose amount can vary as a function of the fuel used.

Moreover, the use of these boilers requires considerable energy resources and has high costs for operation in addition to the drawback consisting in the release of a quantity of hot exhaust gases at high temperature into the environment, which gases still have heat energy that is dispersed into the environment, altering the surrounding bioclimate.

SUMMARY OF THE INVENTION

The aim of the present invention is to solve the above-mentioned technical problems, eliminating the drawbacks of the cited background art, by providing a device which allows the reduction of emissions of particulates and pollutants and the reduction of the temperature of the exhaust gases released from flues and simultaneous recovery of part of the heat energy of the exhaust gases.

Within this aim, an object of the invention is to provide a device that allows reduction of the output temperature of the exhaust gases from the stacks or flues.

Another object of the invention is to make it possible to improve the energy balance of industrial/civil heating systems by lowering their operating costs.

Another object is to obtain a device that is effective, structurally simple, has low manufacturing costs and can be provided with conventional known systems.

This aim and these objects, as well as others which will become better apparent hereinafter, are achieved by an energy recovery apparatus, characterized in that it comprises at least one tubular element and/or a container, which are arranged at a portion of a stack or flue and are provided with a duct for feeding water for scrubbing the exhaust gases, said at least one tubular element and/or container having an outlet for collecting the treated water that can be conveyed to a recuperator/heat exchanger.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will become better apparent from the following detailed description of a particular but not exclusive embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:

FIG. 1 is a partially sectional view of a first layout for the apparatus;

FIG. 2 is a partially sectional view of a second layout for the apparatus;

FIG. 3 is a schematic side perspective view of the first tubular element;

FIG. 4 is a partially sectional side perspective view of the second tubular element;

FIG. 5 is a partially sectional side view of the container.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the exemplary embodiments that follow, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other exemplary embodiments.

Moreover, it is noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject of a disclaimer.

With reference to the figures, the reference numeral 1 designates an energy recovery apparatus, consisting of a first hollow tubular element 2, which is elongated and preferably has a substantially cylindrical cross-section with a preferably flat top 2 a, which has, proximately to a first end 3 a and a second end 3 b, a preferably frustum-shaped tapering portion 4 a, 4 b for connection to a first opening and a second opening 5 a, 5 b that have a preferably circular cross-section, respectively for inflow and outflow.

The first and second openings 5 a, 5 b are connected at a portion of a flue or stack, designated by the reference numeral 6, so that the flow of exhaust gases 7 a that enters through the first opening 5 a passes through all of the first tubular element 2 and exits through the second opening 5 b, providing processed exhaust gases.

Inside the first tubular element 2 there is at least one first coil 8, which consists of at least one single tube arranged on a horizontal plane proximately to the top 2 a.

The first coil 8 has a third closed end 9 a, which is arranged proximately to the first opening 5 a, and a fourth end 9 b, which is arranged proximately to the second opening 5 b and is connected to a delivery tube 10 for the water 11 used to scrub the exhaust gases that pass within the first tubular element 2.

The water 11 that is present inside the first coil 8 exits from a series of first holes 12 formed along its entire surface directed at least toward the bottom 13 of the tubular element 2.

The third and fourth ends 9 a, 9 b can be inverted in their arrangement, while the delivery tube 10 has a first portion 10 a which protrudes axially with respect to the first tubular element 2 through the second opening 5 b.

Further, the first tubular element 2 has, at the bottom 13 and preferably in a region that is adjacent to the second opening 5 b, a second hole 14 with which a first drain 15 is associated which is adjacent to the delivery tube 10 so as to be able to convey the water, heated by scrubbing the exhaust gases, to a recuperator/heat exchanger 50 of the type described in EP 1975538 and consisting therefore of a box-like tank 51 which receives water from the drain 15 that almost reaches its lower end.

The tank 51 is provided internally with a set of tubes 52 and, in a lower region, with a valve 53 for selective discharge of water, for example into the sewage system 54.

Moreover, in an upper region there is a duct 55 for overflow and for selective discharge of water for example into the sewage system 54.

Advantageously, the water conveyed in the delivery tube 10 is forced by means of a pump 56 which draws from the upper part of the recuperator/heat exchanger 50 and therefore has a higher temperature than the water that comes from the aqueduct or from a well.

A second tubular element 16 is provided sequentially downstream of the first tubular element 2, is arranged vertically and is interposed again between the flue or stack 6, optionally in an external part of the building.

Advantageously, the part of the flue 6 that is adjacent to a third lower drain opening 5 c is arranged along an axis which is inclined with respect to the longitudinal axis of the second tubular element 16.

The second tubular element 16 is provided internally with at least one second coil 17, which consists of at least one single tube and can be extracted, the third and/or fourth ends 18 a, 18 b being removable.

The second coil 17 extends within the second tubular element 16 until it approximately skims its inner lateral surface 19, forming a series of circular turns which are supported by a locking means 20 of the double comb-like type, which is composed of two pairs of linear flanges 21 a, 21 b which are opposite each other and have a series of seats for positioning and supporting portions of the tube that form the second coil 17.

The locking means 20 is fixed to the second tubular element 16 by means of screws 22, which pass through appropriately provided holes formed in said second tubular element, which once unscrewed allow simultaneous extraction of the locking means 20 and of the second coil 17 by means of a handle 23 that can be gripped by a user since it is arranged transversely at the upper end of the locking means 20.

The second coil 17 is closed at a third or upper end 24 and has second holes 25 that are formed both on the surface directed toward the third or upper end 24 and on the surface directed toward the inner lateral surface 19 of the second tubular element 16.

The fourth lower end 26 of the second coil 17 is connected to the first portion 10 a of the delivery tube 10 for the water used to scrub the exhaust gases that enter through the third opening 5 c.

The second tubular element 16 also has a second outlet 27 for the water that filters the exhaust gases in countercurrent and is arranged below and adjacent to the end of the flue 6 that is connected, along an inclined axis, to the third opening 5 c, so as to be arranged in axial alignment with the second tubular element 16.

The apparatus 1 can further consist, as shown in FIGS. 2 and 5, of a container 28 which is arranged downstream of the second tubular element 16 and also is interposed between the stack or flue 6, optionally in an external part of the building.

The container 28 preferably has a box-like shape that is open in an upper region so as to form a closed bottom 29 and an open top 30, with the interposition of a body 31 that is shaped substantially like two different frustums that are arranged opposite each other at their larger end faces.

Water 11 can thus be stored inside the container 28 at a desired level 32.

The container 28 has, laterally to the body 31, at least one first duct 33 for conveying the exhaust gases which enter through a fourth opening 5 d which is contiguous, with the interposition preferably of a fan 34, to the flue or stack 6.

The first duct 33 has a shape that causes its end 35 located within the container 28 to arrange itself below the level 32 of the water contained therein.

The container 28 further has, laterally to the body 31 but in a region that lies above the level 32, a second duct 36 for feeding water, which can be of the recirculation type for cooling that arrives for example from means adapted for heat recovery, such as sewage system heat recovery.

The container 28 further has, laterally to the body 31 but in a region that approximately corresponds to the level 32, a third outlet 37 for the water for maintaining the level 32; this is therefore an overflow for return for example to means suitable for heat recovery, such as sewerage system heat recovery, or to the recuperator/heat exchanger 50.

FIG. 1 also illustrates a further third tubular element 38, which is interposed between two ends of a stack or flue 6 and provided internally with at least one third removable coil 39, which is provided with a first connector 40 which conducts water to a boiler 41 and with a second delivery connector 42 for receiving water from the recuperator/exchanger 50.

The water that flows in the third coil 39 is heated by drawing heat from the exhaust gases that skim such coil and raises the temperature of the water that is about to be conveyed into the boiler 41, further improving efficiency.

Any condensation that might form outside the third coil 39 is conveyed, through a fourth outlet connection 43 that is interconnected to the first drain 15 that leads into the recuperator/heat exchanger 50.

The operation of the apparatus is as follows.

When a burner starts to operate, for example the burner of the boiler 41, the exhaust gases that originate from the combustion are guided into the stack or flue, and along their path they pass through the various components of the devices and are thus scrubbed before exiting into the atmosphere.

When the burner is turned on, a pump is in fact actuated which draws water 11 from the recuperator/heat exchanger 50 and conveys it along the delivery tube 10 until it reaches the first coil 8 and the second coil 17.

The water 11 flows through the first and second coils along their entire length, exiting through the first and second holes 12, 25: a shower of drops is thus formed which, in falling, passes through the flow of exhaust gases that passes through the respective tubular element.

A similar function is observed in the container 28 and heat recovery is achieved also with the device 38.

The amount of water used to spray the exhaust gases and the pressure of such exhaust gases are balanced so as to avoid causing any problems of pressure or negative pressure to the combustion.

Further, the pump continues to operate and therefore draw water as long as the burner is operating: shutdown of the burner is in fact followed by the halting of the pump within a few seconds.

More precisely, the water in this manner is able to lower the temperature of the exhaust gases, which is harmful for the environment and which without the device is approximately 70/90° C. if it exits from condensation boilers and approximately 120/400° C. if it exits from boilers which are of the non-condensing type or from ovens or dryers.

Moreover, the water is able to capture a substantial fraction of the suspended particulates, which are thus guided and conveyed with the treated water into the outlet to the recuperator/heat exchanger for heat recovery.

In practice it has been found that the invention has achieved the aim and objects cited above, an apparatus having been obtained which, by scrubbing the exhaust gases, makes it possible to eliminate from them a substantial fraction of the particulates and pollutants and at the same time allows a strong reduction of the output temperature of such exhaust gases, increasing the temperature of the scrubbing water, which can be conveyed to a recuperator/heat exchanger for heat recovery.

The materials used, as well as the dimensions that constitute the individual components of the invention, may of course be selected by the skilled person so as to be the most pertinent according to specific requirements.

The various means for performing certain different functions need not certainly coexist only in the illustrated embodiment but can be present per se in many embodiments, including other possible embodiments that are not illustrated and which are within the scope of the appended claims.

The characteristics indicated as advantageous, convenient or the like may also be omitted or be replaced with equivalents.

The disclosures in Italian Patent Application No. TV2009A000025 from which this application claims priority are incorporated herein by reference. 

1. An energy recovery apparatus, comprising: at least one tubular element, which is arranged at a portion of a stack or flue and is provided with a delivery for feeding treatment water for scrubbing exhaust gases, said at least one tubular element having an outlet for collecting the treatment water for conveyance to a recuperator or heat exchanger.
 2. The apparatus of claim 1, having a first hollow said tubular element, which is elongated and has a substantially cylindrical cross-section with a flat top, said tubular element having, proximate to a first and a second end thereof, a frustum-shaped tapering portion for connection to a first inflow opening and a second outflow opening that have a circular cross-section, said first and second openings being connected at portions of the flue or stack so that a flow of exhaust gases that enters through said first opening passes through all of said first tubular element and exits through said second opening, as processed exhaust gases.
 3. The apparatus of claim 2, comprising: at least one first coil provided within said first tubular element, said coil consisting of at least one single tube that is arranged on a horizontal plane proximate to the coil top, said first coil having a third closed coil end, which is arranged proximate to said first opening, and a fourth coil end, which is arranged proximate to said second opening; and a delivery tube that constitutes said delivery and is connected to the first tubular element for feeding the treatment water used to scrub exhaust gases that pass through said first tubular element; a series of first holes that are formed along an entire surface directed at least toward a bottom of said tubular element; the treatment water fed inside said first coil exiting from said series of first holes, said delivery tube having a first portion that protrudes axially with respect to said first tubular element through said second opening.
 4. The apparatus of claim 3, further comprising a heat exchanger, wherein said first tubular element has, at said bottom and in a region that is adjacent to said second opening, a second hole with which a first drain is associated which is adjacent to said delivery tube, so as to be able to convey the treatment water, heated by scrubbing of the exhaust gases, to the heat exchanger, said heat exchanger consisting of a box-shaped tank and receiving water from said first drain that reaches near a lower end of the tank, said tank being provided internally with a set of tubes and in a lower region with a valve for selective discharge of treatment water into a sewage system, and wherein an overflow duct is provided above said tank for overflow and for selective discharge of treatment water into the sewage system.
 5. The apparatus of claim 4, comprising a second tubular element that is provided connected sequentially downstream of said first tubular element, is arranged vertically and is interposed between flue or stack portions, in an external part of a building, a further part of the flue that is adjacent to a third lower drain opening of the second tubular element being arranged along an inclined axis that is inclined with respect to a longitudinal axis of said second tubular element, said second tubular element being provided internally with at least one second coil, said second coil consisting of at least one single tube that is extractable from said second tubular element, the third and/or fourth ends whereof are provided removable.
 6. The apparatus of claim 5, wherein said second coil is provided so as to extend within said second tubular element until skims an inner lateral surface thereof, said second coil comprising a tube forming a series of circular turns which are provided with and are supported by a locking means of a double comb shape, said locking means being composed of two pairs of linear flanges, which are opposite each other and have a series of seats for positioning and supporting portions of the tube that form the second coil, said locking means being provided with a handle arranged transversely at an upper end of the locking means and being fixed to said second tubular element through screws, which pass through suitable holes formed in said second tubular element, said screws allowing, upon unscrewing thereof, simultaneous extraction of said locking means and of said second coil by means of said handle that can be gripped by a user.
 7. The apparatus of claim 6, wherein said second coil is closed at an upper end thereof and has second holes that are formed both on a surface of the second coil directed toward said upper end and on a surface of the second coil directed toward the inner lateral surface of said second tubular element, a lower end of said second coil being connected to said first portion of said delivery tube, said second tubular element having a second outlet for treatment water that filters exhaust gases in countercurrent, said second outlet being arranged below and adjacent to a portion of the flue that is connected, along an inclined axis, to said third opening, said second outlet being in axial alignment with said second tubular element.
 8. The apparatus of claim 4, comprising a container which is arranged downstream of said first tubular element and is interposed between portions of the stack or flue, in a portion that is in an external part of a building, said container having a box shape that is open in an upper region and has a closed bottom, an open top, and a body that is interposed between the bottom and top and is shaped substantially like two different frustums which are arranged opposite to each other and in contact at their larger end faces, treatment water being storable within said container at a desired level, said container further having, laterally to said body, at least one first duct for conveying exhaust gases, which enter through a contiguous opening of said body, a fan being further located at said contiguous opening for conveying the exhaust gases in the first duct, to the flue or stack.
 9. The apparatus of claim 8, wherein said first duct has an end located within said container shaped so as to arrange itself below a level of treatment water contained therein, said container having, laterally to said body, in a region above the water level, a second duct for feeding treatment water, recirculated for cooling, that arrives from a heat recovery, said container further having, laterally to said body in a region that approximately corresponds to the water level, a third drain outlet for the treatment water for setting and maintaining said water level, said drain outlet forming a treatment water overflow for water return to a heat recovery or to the recuperator/heat exchanger.
 10. The apparatus of claim 5, comprising a third tubular element, which is interposed between portions of a flue or stack, said third tubular element being provided internally with at least one third extractable coil, which is provided with a first connector conducting treatment water to a boiler, and with a second delivery connector, for receiving treatment water from the heat exchanger, a fourth outlet connection that interconnects said first drain which leads to said heat exchanger and said third tubular element, being provided for conveyance of condensation that might form outside said third coil to the heat exchanger. 